1. Field of the Invention
The present invention relates to an image processing apparatus such as a digital camera which is provided with a handwriting input section and which records captured images in the form of digital signals, and an image processing method, and a storage medium storing a program for executing the image processing method.
2. Description of the Related Art
A digital camera which is provided with a handwriting input section is conventionally known. A digital camera section and a handwriting input section of the conventional digital camera will be described below in this order.
FIG. 11 is a block diagram schematically showing the configuration of a conventional digital camera provided with a handwriting input section that enables a user to input handwritten characters or designate positions using a touch pen.
After the power is turned on, when an operation mode switch is set to a photographing operation mode, a camera module 17 including a CCD 12 and a CCD control section 14 is initialized and enabled to shift into a state called “monitor” or “finder” to start operation of an LCD display section 30 that is an electronic view finder for allowing the user to check an object during the photographing operation mode operation. A flow of these operations will be described below.
First, optical information on an object captured through a group of camera lenses 10 is converted into an electric signal by means of the CCD 12 which is of the progressive scan type. The converted or analog signal is subjected to a noise removal process and a gain process and then subjected to A/D conversion, for example, into a 10-bit digital signal by means of the CCD control section 14, which is then transmitted to an image processing section 16. The image processing section 16 carries out processes such as automatic white balancing, AE, or corrections for stroboscopic photographing, or signal conversion into a Y, Cb and Cr signal format (Y: luminance signal, Cb and Cr: color difference signals).
In order to increase a display processing speed and since the LCD display section 30 has a display resolution of, for example, about 320×240 pixels, the converted signals in the Y, Cb and Cr signal format are further converted by a CPU 18 into data of a reduced size of 320×240 pixels instead of all pixels, that is, 640×480 pixels using a decimation process. The signals are then written onto an area VRAM 22e reserved in a RAM 22 for storing image data to be displayed and are regularly output to an LCD control section 100 using DMA (direct memory access), that is, a function of the CPU that transfers data between memories or between a memory and a peripheral device with a minimum number of steps.
The LCD control section 100 converts the received Y, Cb and Cr signals into RGB digital signals and outputs them to a display driving section 28. The LCD display section 30 receives the output signals from the display driving section 28 and displays an image of the object.
The above processes are continuously repeated with a cycle of 1/30 seconds with which image data are output from the CCD 12, to allow the image of the object to be always monitored on the LCD display section 30.
Next, a description will be given of a flow of a process in a photographing operation mode and recording operation mode for capturing and recording an image.
To capture an image, an operator monitors the image in the photographing operation mode and depresses a shutter switch (SW) 32 in timing he desires. If the shutter switch SW 32 is depressed, various camera settings such as automatic white balancing, AE, and corrections for stroboscopic photographing which are controlled within the image processing section 16 are locked at the current set values, and the operations of the LCD control section 100, the display driving section 28, and the LCD display section 30 are stopped to reduce the processing load on the CPU 18.
Although the above-mentioned view finder process captures only a signal of the reduced number of pixels of the decimated image in order to increase the display processing speed, a full VGA (640×480 pixels) image is required as a captured image. The CPU 18 thus captures Y, Cb and Cr signals corresponding to the VGA pixels and writes data in these signals onto an image data expanding area 22a in the RAM 22 after execution of predetermined processes on the data by the image processing section 16.
The CPU 18 subjects the data to an image data compressing process according to the JPEG Standard, subsequently adds numerical data such as desired numbers or date data to the obtained data as a file name, and then writes them into a desired folder in this apparatus created inside a data storage section 102 (for example, a flash memory). Captured images are thus sequentially written into this folder.
Next, a description will be given of a flow of a process in a reproducing operation mode for reproducing the captured image for display.
When the power is turned on or when the operation mode switch is operated to switch the photographing operation mode to an image reproducing mode, the CPU 18 actuates the LCD display section 30, that is, the electronic view finder for allowing the user to check the captured image, to enter a data waiting state. The CPU 18 causes a group of arbitrary folders in this apparatus to be displayed to prompt the operator to select one of them. After a folder is selected, if a display image file is designated, the designated image is displayed over the entire screen as a VGA image. Without any designation, compressed image data files for an arbitrary number of images that can be displayed in a list as thumb-nail images (for example, 80×60 pixels) are read out from the data storage section 102 in order of photographing date starting with the earliest one, and are written onto the image data expanding area 22a in the RAM 22. Then, an image data expanding process, that is, a process of converting the compressed data corresponding to the VGA pixels according to the JPEG Standard into the original data (Y, Cb and Cr data) is carried out, and the original data obtained by the data expanding process are converted into data of 320×240 pixels using a decimation process if the designated image is to be displayed, or are subjected to a decimation process for the thumb-nail display with 80×60 pixels if these images are to be displayed in a list. The thus processed data is subsequently output to the LCD control section 100.
The LCD control section 100 converts the received Y, Cb and Cr signals into RGB digital signals and writes the RGB data onto the area VRAM 22e that stores image data to be displayed, at addresses corresponding to designated desired display positions (coordinates), so that the data can be displayed at these display positions. Further, a warning of an amount of power remaining in the battery, various control messages, and others are also all converted into RGB data and written onto the area VRAM 22e at corresponding addresses.
After all data required for the display are written onto the area VRAM 22e, the LCD control section 100 outputs the RGB signals on the area VRAM 22e to the display driving section 28. On receiving the output signals from the display drive signal 28, the LCD display section 30 displays the image of the object.
In FIG. 11, reference numeral 101 designates a read only memory (RAM) that stores a control program to be executed by the CPU 18, and a power supply voltage output from a battery 35 as a power supply is adjusted by a DC/DC converter 36 to a value that is appropriate for various parts before being supplied thereto.
Next, the handwriting input section will be explained.
Conventional electronic I/O-integrated handwriting equipment is comprised of a display section and an input section which overlap each other and is operated with input means such as a pen or the operator's fingertip. This construction can be operated in the same manner as when characters or graphics are written or drawn on paper, by operating software-based switches on a display screen, displaying an input trace, or causing the equipment to recognize characters.
Further, if an application program is executed with such equipment, the operator uses a pen or his fingertip to select and execute a desired program while depressing icons or menus displayed on the small-sized display section.
When the operator touches a transparent tablet unit with a pen, control is provided such that voltages in X and Y directions corresponding to a point depressed by the pen are converted into digital data, and X and Y coordinates are detected based on these X and Y digital values, so that a dot on the LCD panel corresponding to the detected X and Y values is lighted or a key switch or a command displayed at a position corresponding to the detected X and Y coordinates is selected. The fixed display section is used to select main functions, and when it is depressed with the pen or the operator's fingertip, functions located at the depressed positions are read out, for example, from the ROM and processes or displays corresponding to the readout functions are carried out on the LCD panel
Since, however, the above described conventional digital camera has only one display means, the process of reproducing the captured image and the process of monitoring the object for photographing cannot be simultaneously executed. Further, if part of an image being captured is to be pasted to a previously captured image, first, the current image must be captured and saved, and then the current and past image data must be transferred to the digital camera or a personal computer and synthesized using exclusive software.
Some of the latest digital cameras have a function like “Print Club” (an automatic camera installed in a town to provide small instant arranged photographs depending on a user's operation) which displays previously designed image data called “a frame” on an LCD display section and then displays a monitored image therein so that at the time of photographing, the image is loaded into the camera together with the frame. The frame, however, is fixed and cannot be freely designed by the operator. Thus, if a captured image is desired to be synthesized with a frame image designed and created by the operator, this cannot be realized unless the captured image is loaded into a personal computer where expensive software is used for image synthesis.